1. Field of the Invention
The present invention relates generally to the fields of obstetrics and/or perinatal medicine. More particularly the invention relates to repair of pre-parturition rupture of the amniotic fluid sac.
2. Description of Related Art
Premature rupture of membranes (PROM) during the second and early third trimester of human pregnancy creates a management dilemma for obstetricians. There are currently many management protocols for PROM. Recent literature argues the risks and benefits of tocolytic agents, antibiotics, and corticosteroid injections primarily for delaying delivery, preventing intraamniotic infection, and enhancing fetal maturity, respectively, in the event of almost certain preterm delivery. However, to date, no true accepted treatment for PROM exists. Medline searches of this topic reveal only scant data in Italian studies on intracervical instillation of fibrin glue, and Japanese attempts at mechanical blockage of the cervix using double balloon-tipped catheters.
The ideal therapy for PROM in the absence of chorioamnionitis, and deciduitis (infections implicated in premature rupture and preterm labor) would seem to be to recreate an intact amniotic fluid sac using a benign sealant injected into the amniotic sac using needles no bigger than those now commonly used for amniocentesis. By recreating the integrity of the amnion, such a technique would provide a barrier to ascending infection from the normal bacterial flora of the cervix and vagina commonly isolated in most all obstetric and gynecologic infections. Such a technique would also allow reaccumulation of normal amniotic fluid volumes, thus protecting the fetus from compression of its own umbilical cord.
Chicken egg white is a cross species analog to amniotic fluid, providing protection, cushioning, and nutritive substances essential to the survival of the unborn chick. The cross linking of this colloid substance at the site of membrane rupture in the human gestation may provide an adequate sealant in the event of PROM. The inherent properties of egg white colloid include immiscibility with water (hydrophobic), thus creating a bolus effect when encountering the leakage site after injection into a water filled cavity. The most gelatinous portion of the thick egg white component is of substantially low enough viscosity to allow injection via a standard 18 to 20 gauge spinal needle commonly used for amniocentesis.